1. Field of the Invention
The present invention relates to a herbal composition and, more particularly, to a herbal composition for relieving symptoms of diabetic retinopathy. The present invention further relates to a method for relieving symptoms of diabetic retinopathy by administrating the herbal composition to a subject in need.
2. Description of the Related Art
Diabetic retinopathy is a complication of diabetes, which is caused by hyperglycemia-induced incompetence of the vascular walls, resulting in microvascular retinal changes, such as dysfunction of blood-retinal barrier and hyperpermeability of capillary circulation. Moreover, diabetic retinopathy is the leading cause of blindness in patients with diabetes.
Conventional methods for relieving symptoms of diabetic retinopathy include laser surgery, vitrectomy and intraocular injection of corticosteroids. However, all of the conventional methods belong to invasive treatments but cannot completely cure diabetic retinopathy. Therefore, patients with diabetic retinopathy have to monitor blood glucose level to adapt to maintain normal blood glucose level (euglycemia) all the time. Furthermore, intraocular injection of corticosteroids can also lead to side effects such as steroid-induced disorders. In light of this, it is necessary to improve the conventional method for relieving symptoms of diabetic retinopathy.
Dendrobium officinale not only can be used to lower the blood glucose level, improving diabetes-related disorders, but also can be used as the active ingredient for retinal disorders. However, Dendrobium officinale cannot be used for relieving symptoms of diabetic retinopathy effectively.